Stereotype plate holding and tensioning mechanism



E. w; WORTHINGTON March 25, 1941.

- s'rnnsonrx'rmrs HOLDING AND TENSIONIKGIBGHANISI 3 Sheets-Sheet 1 Filed March 28, 1939 Y 7 I A U 2" v'") 'mwll a, \W 5/ Maya. 25, 1941.

E. W. WORTHINGTON STEREOTYPB PLATE HOLDING AND TENSIONING IEGHAN'ISM Filed March 28, 1939 3 Sheets-Sheet 2 l I l I ll I VENTOR W 7 AQTTOIIRNEYS March 1941- E. w. WORTHINGTON .2 6. 0

s'ransourn nus HOLDING 1mm rrmsrou me MECHANISM Filed uarch 28, 19:59 3 Sheets-Sheet s The accompanying drawings,

,herein and constituting a parthereoi', illustrate Patented Mar. 25, 1941 UNITED STATES PATENT OFFICE. amaze sTEaEo'rn-E rm'rE nomine arm msromc, mcnmsu Einory W. Worthington, Chicago, 111-, assigner to- 'l'heGessri-intingrreucompanzchicago,

a corporation of Illinois Application m as, me, mm. 204,514

s Claims. (on. 101418) The invention relates to new and useful improvements in mechanisms for holding and ap-' plying peripheral tension to printing plates upon l Objects and advantages of the invention will be set iorth in part hereinafter and-in part will be obvious hereirom, or may be learned bypractice with the invention, the same being realized and attained by means of the instrumentalities l and combinations pointed out in the appended claims. v

The invention consists in the novel parts. constructions, arrangements, combinations and improvements herein shown and described.

referred to 'one embodiment of the inventiomand together with the description, serve toexplain the-prinotthattyl ciples oi the invention.

' 5 Oithe drawings:

mg. 1-1: a transverse section through-aplate cylinder 01 a press and showing an embodiment oi-myinvention; o I Fig.2isan end view or the plate cylinder look 30 ing irom the leitin1'l8.3; 1

-- Fig.3isaplanwithpartsbrokenaway,lookingatthe'plate cylinder of m..1inthedirection oiarrow-A (Fig-1);

I'ig. 4 is a similar view, lookingat the plate 35 cylinderoil'lgJinthedirectionotthearrowB: Fig.5isasectiontakenon1ineI-lo1lig.3;

.Obiectsoi the invention are to provide simple, sturdy and powerfully operating peri tensioningand holding means for the plate; to provide such means so designed and so located spaced in the cylinder so as to afford room 5 for mounting and operating the especially poweriul spring tensioning mechanism which is applied along the tail end. of the plate to tension the platepcripherally about the cylinder; to provide simple. and powerful in tor retracting the tail end plate-engaging jaw against its tensioning V springto release the plate, andautomatically' holding it in the retracted position; to provide 2 accurate and precise peripheral positioning means for the head Na e-m ma clamp; and l5 .to provide these means applicable to plate cylin- Referring now in detail to the embodiment of the invention illustrated by way oi example in the accompanying drawings. the invention is \lppliedtoal iflnlpreescylinderoithetubular oroneplatearoimdtype Theplateoylinderi isahown'with'aatereotypc plate encirclingthe 'cylinderiorthe greaterpartotitecircumierenca- 'meansnearandalong'the'headandtailoithe a the recess i8. front edge or e {HOOK-like undercut bar 5 on the plate 2. The jaw i5 is preferably integral for the entire width of the plate, Means are provided for minutely and precisely positioning this holding means for the plate head, and as embodied (Figs. 1 and 4) there are formed on the rear, radial face of the bar H a plurality of wedge-like projections i'l. Located in said recess ii in the plate cylinder and behind the bar i4 is a longitudinally-extending bar IS, the rear face of which engages the undercut wall IQ of the recess l3. On the front face of the bar i8 are wedge-shaped members 20 which engage with the wedge faces I I of the bar l4, whereby longitudinal sliding movement of the bar i8 against the back wall I! of the recess will move the plate-engaging bar i4 forwardly or per-' mit backward movement thereof, so as to precisely position the head of the plate with reference to the cylinder.

Means are provided for moving and positioning the bar it longitudinally of the cylinder for the purpose stated, and as embodied a screwrod 22 is journaled at 23 in the plate cylinder I, and is in screw-threaded engagement with one end of the bar id. The screw rod is held against longitudinal movement in its bearing in the plate cylinder by means of a collar 24 on one side of the bearing and a turning head 25 on the exterior of the cylinder end. The bar I4 is resiliently held with its wedge faces I! in engagement with the wedge faces 20 of the bar l8 by resilient means, comprising a plurality of compression springs 28 nested in bores in the L- shaped foot as of the bar l4, the springs pressing against cylindrical contact pieces 30 which en-' gage the forward wall of the undercut portion v of the recess i3.

Referring now to the embodied means for engaging with and placing powerful peripheral tension on the tail end of the stereotype plate, a bar 35 is positioned in a longitudinally-extending recess 36 formed in the plate cylinder. The bar 35 has along its upper edge a hook-like jaw or portion 31 that engages behind and underneath the bar 1 on the plate 2. The jaw 31 likewise is preferably integral for the width of the plate. This plate engaging bar is movable under powerful resilient pressure to tension the plate. As

embodied, the bar 35 has at either end pintles or spindles 39, journaled in bearing blocks 38, mounted at the ends of the recess 36 in the plate cylinder, so that the jaw 31 moves angularly into and out of engagement with the stereotype plate 2, and the resilient tensioning action on the stereotype plate is exerted substantially tangentially of the plate cylinder at the'locus of the bar I. The bar has an integral foot 4| extending rearwardly therefrom within the recess 36, Powerful springaction is exerted on the foot 4| tending to rotate the bar 38 around its axis 39 in the direction to tension of the plate, and as embodied, a plurality of spiral compression springs 43 are nested in openings which oi the plate-tensioning device. The closure block is held in place on the cylinder by screws 49.

The embodied means for retractively rocking the bar I! about its pivotal bearings against the spring tension to release the stereotype plate,

comprises an arm 54 keyed on one of the pintles 39 of the bar 35, the arm having a cam roller 55 journaled in the end thereof. The cam roller 55 runs on a cam track 56 formed in a ring 51, which is rotatively mounted on a shaft 58 of the plate cylinder i. The ring 51 has a cutaway portion 64 to give clearance of the jawactuating mechanism (Figs. 2 and 5). Means are provided for holding the clamping jaw in this retracted position, and for this purpose at the end of the cam track 56 is a detent depression 60 into which the cam roller 55 runs, thereby holding the plate-engaging hook 3! in retracted position against the springs 43 while a plate is removed from the cylinder and a new plate is put on. When the new plate is in place, the cam ring 51 is moved in the opposite direction, jaw 31 engages the new plate and places it under peripheral tension. The means formanually rotating the cam ring 31 to move the part 31 into and out of plate engaging position comprises a boss 62 having an axial bore 63 adapted to take a hand bar or other actuating tooi.

The invention in its broader aspects is not limited tothe specific mechanisms shown and described but departures may be made therefrom within the scope of the accompanying claims without departing from the principles of the invention and without sacrificing its chief advantages.

What I claim is:

1. In combination in'a rotary printing press, a stereotype plate cylinder, circmnferentially movable means for holding the head end of the plate to the cylinder, means for peripherally tensioning the plate about the cylinder, said means including a pivotally mounted jaw adapted to engage the plate near its tail end, springs mounted within the cylinder and resiliently acting to move the jaw to exert peripheral tension on' the plate and means for retractively moving the law in the opposite direction to release the plate,'said means comprising an arm connected to and concentric with the mounting of said jaw,

a cam for actuating said arm, and means for holding the jaw in the retracted position.

2. In combination in a rotary printing press, a stereotype plate cylinder, circumferentially movable means for holding the head end of the plate to the cylinder, means for peripherally tensioning the plate about the cylinder, said means including a member pivotally mounted within the cylinder and having a Jaw which engaga the plate near its tail end throughout'substantially the entire width of the plate, springs nested within the cylinder and resiliently acting to move said member about its pivotal mounting to cause the jaw to exert peripheraltension on the plate and means for moving said member in the opposite direction against its springs to disengage the law from the plate, said means comprising an arm connectedto and concentric with the pivotal mounting of said member and a cam for actuating said arm.

3. In combination in, a. rotary printing press, a stereotype, plate cylinder, circumferentially movable means for holding the head end of the plate to the cylinder, means for peripherally tensioning the plate about the cylinder, said means including a pivotally mounted jaw adapted to engage the plate near its tail end, resiliently acting means for causing the jaw to exert peripheral tension on the plate, and means for retractively moving the jaw in the opposite direction to release the plate, said means comprising an arm connected to and concentric with the mount- 7 ing of said jaw and a ring rotatively mounted on the plate cylinder shaft, and having a cam surface pfor moving said am, said ring having a detent adapted to engage said arm to hold the cumferentially of the cylinder at one end of the plate and resilient means carried by the cylinder and engageable with the other end of the plate for resiliently tensioning the plate on the cylinder to hold it thereon. I

5. In combination in a rotary printing press. a stereotype plate cylinder, and means for holding and peripherally tensioning a plate about the cylinder, said means comprising a longitudinal bar mounted in a recess in the cylinder and having a plate engaging jaw, wedge members on the rear face of said bar, a second bar alongside and behind said first-mentioned bar and having wedge members on said first-mentioned bar, and means including a screw-threaded member rotatively mounted on the cylinder and having threaded engagement with said last-mentioned bar longitudinally of the cylinder to effect movement of said jaw circumferentially of the cylin- 3 and tensioning a stereotype plate peripherally about the cylinder comprising means engaging the plate 'near its head end including a member plurality of wedge members spaced therealong, a

cooperating member mounted on and extending longitudinally of the cylinder, having wedge -members cooperating with said first-mentioned sioning means mounted on the cylinder and engaging the plate near its tail end including a member pivotally mounted on the cylinder and having a jaw adapted to engage the plate, means.

including springs nested within the cylinder and acting to move said pivotally mounted member about its pivot to move said jaw in one direction to exert peripheral tension upon the plate and means for moving said jaw in the opposite direction to release the plate from the cylinder, said means comprising an arm fixed to said member concentrically with its pivot and a cam for actuating said arm, rotatably mounted on the plate cylinder shaft.

7. In combination in a rotary printing press, a stereotype plate cylinder, circumferentially movable means for engaging and securing the plate to the cylinder-near its head end, means for circumferentially-moving said means to vary the position of the plate on the cylinder, and reslliently acting means engageable with the plate near its tail end for circumferentially tensioning the plate to hold the plate to the cylinder.

8. In combination in a rotary printing press, a stereotype plate cylinder, circumferentially movable means for holding the head end of the plate tothe cylinder, means for peripherally tensioning the plate about the cylinder, said means including a'jaw adapted to engage the plate near its tail end, springs mounted within the cylinder and resiliently ,actingto move the jaw to exert peripheral tension on the plate, and means for retractively moving the jaw in the opposite direction to release the plate.

EMORY W. WORTHINGTON. 

